Collapsible crown block



F eb. 8, 1944.

J. w. M CLATCHIE COLLAPSIBLE CROWN BLOCK Filed Dec. 4, 1940 2Shegts-Sheet 1 Jam )1. MCCMTOV/t',

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of a derrick and Patented Feb. 8, 1944 UNITED. STATES PATENT OFFICE.msmizi tit... Bro-(K John W. MacClatchie, Los Angeles. Calif., assignorto MacClatchie Manufacturing Company of California, Compton, Calif., acorporation of California Application December 4, 1940, SerialNo.368,482

3 Claims. (orjgs i isn) My invention relates to collapsible crown blocksfor oil well derricks and the like.

A crown block is mounted on the water table provided with a number ofsheaves over which the cable line is reeved-for supporting the travelingblock. The present oil well production practice is to allow the crownblock to remain on the Water table during the entire time that the Wellis on production, even though the crown block is only used at infrequentintervals. This is due to the fact that present day crown blocks must bedisassembled in order to pass through the openingin the water table of aderrick and must then be reassembled before use.

The object of my invention is to provide a collapsible crown block whichmay be easily and quickly mounted on the water table as a unitin orderto make it practical to raise a crown block into position on the watertable whenever'the use of a crown block is required and to remove thecrown block after the work has been completed, rather than to allow thecrown block to remainon the water table during the entire period thatthe well is on production.

Another object of my -invention is to provide a crown block in which thecable line is adapted to be reeved around the sheaves of the crown blockand the sheaves of the traveling block before the crown block is raisedinto position in the derrick.

Another object of my invention is to provide a collapsible sheavesupporting member which in collapsed or retracted positionis'adapted topass through the opening in the water table of a derrick and which inextended position is adapted to extend across said opening in the watertable.

Another object of my invention is to provide a collapsible crown blockwhich may be mounted into position in the derrick without firstdisassembling the crown block, and then reassembling the crown blockafter the parts have been raised into position in the derrick.

Another object; of my invention is to provide a collapsible crown blockin which the cable lines may be reeved around the sheaves of the crownblock and the sheaves of the traveling block before the crown block israised into position in the derrick, so that the crown block incollapsed position with the cable lines reeved around the sheaves may beraised through the opening in the water table, after which the crownblock is adjusted to extended position, and lowered on the water tablewith the crown block and the cable line ready for use.

' Although my invention relates primarily to crown blocks for use inconnection with produc-' ing wells, the invention may be used inconnection with crown blocks for use in the drilling of wells.

My invention has many other objects, advantages, and features, some ofwhich, with the foregoing, will be set forth at length in the fol--.lowing description where I shall describe certain forms of my inventionfor use in connection with producing wells, which I' have selected forillustration in the drawings accompanying and forming a part of thepresent specification.

Referring to the drawings: 1 Figure 1.15 a plan view showing the crownblockin retracted position coming up through the water table opening.

Figure 2 is a plan view showing the crown block in extended position andin place on the water table. I Figure 3 is a side elevation of thecollapsible crown block in extended position in place on the watertable, with the retracted position indicated on dotted lines. Figure 4is a section taken on the line of Figure 3.

Figure 5 is a side elevation of a hinged crown block in position for useon the water table, with the collapsed position shown in dottedlines.

Figure 6 is a section taken on theline 6- -6 of'Figure 5. W I 1 a In thedrawings the numeral Ill indicates a'n opening in a water table II atthetop of a deer rick 12. The water: table is formed by "water tablebeams Hand [4, around which beams is usually a working platform (notshown). The opening I0 is square in the usual derrick. The water tablebeams 13 provide a support for the crown block.

In the form of my invention shown in Figures 14 inclusive, the crownblock comprises supporting members [5 which are adapted to be extendedand retracted longitudinally and sheaves l6 mounted on said supportingmembers. Any number of sheaves may be mounted on the supporting membersH5 in the usual manner, that is, on bearings and with means for readilyadjusting the position of the sheaves on the supporting members.

As shown in Figures 1-4, the supporting member [5 may comprise I-beamsI1, I 8 and I9, connected together with I-beam spacers 20, extensibleand retractable members 2| and supporting blocks 22. The extensible andretractible members 2| are secured to the beams l1 and I9. Said members2| are shown in extended position in Figures 2 and 3 and in retractedposition in Figure 1 and in dotted lines in Figure 3.

Means are also provided to limit the outward movement of the extensiblemembers 2|. An instance of this arrangement is shown in Figures 3 and 4in which the extensible members 2| are provided with longitudinal slots23, and bolts 24 are inserted through said slots 23 and holes in thebeams l1 and I9, the outward movement of said extensible members 2|being limited .by the engagement of the inner ends of said longitudinalslots 23 with said bolts 24.

The operation of the collapsible crown block of my invention is asfollows:

Before the crown block is raised into position on the water table beamI3, a cable line 25 from usual hoisting drum (not shown) may be reevedaround the sheaves l6 and the sheaves of a usual traveling block 25a,and the other so-called dead-end ofsaid cable line secured at the baseof the derrick in any usual manner (not shown).

The extensible members 2| are moved into retracted position. The crownblock is then raised through the water-table opening ID by means of acable line supported by the usual gin, sole or in any other manner. The.extensible members2| are .then moved to extended position as shown inFigures 2 and 3 and the crown block is lowered on the water .table.beams [3, after which the cable line 25 is readyfor use.

Obviously, the. crown blockmay be raised into position without the cable.line 25 reeved around the sheaves M5,. and the cable line 25 reevedaround said sheaves l6 and the sheaves of the traveling block 2511 afterthe .crown block is in position on the water table beams l3.

Obviously, instead of securing the so-called dead line of the cable line25 at the base of the derrick, said end of said cable line 25 may besecured to the traveling block 25a, which is frequently done in presentday practice.

In the modification of my invention shownin Figures and 6, the sheaves[6 are mounted on beams 30 and 3| which are hinged together by means ofa hinge plate 32 mounted on a hinge pin 33.

The beam 30, which may bein the form of .an I-beam as shown in theFigures 5 and 6, is bored to take the reduced shank 34 of the hinge pin3.3, and the hinge plate 32 is bored to receive an enlarged portion35 ofsaid p n.

. The construction of the remainder of this modification, the use andoperation of said crown block are deemed to be apparent from thedescription set forth herein in connection with the form of theinvention shown in Figs. 1-4, inclusive, and will therefore not be setforth herein.

From the foregoing description taken in connection with the accompanyingdrawings, the uses, advantages, and operation of my invention will bereadily understood'by those skilled in the art to which the'inventionappertains. While I have described the forms of my invention which I nowconsider to be the best embodiments there- 'of, I desire to have itunderstood that the forms shown are merely illustrative and that theinvention is not to be limited to the details disclosed herein, but isto be accorded the full scope or the appended claims.

I claim:

1. A crown block structure adapted to be positioned on top of the watertable of a derrick comprising a plurality of sheaves, means forsupporting said sheaves, said means comprising a plurality of partsmovable with respect to each other from an'extended position in linewith each other to a collapsed position, said parts in collapsedposition enabling said means to be moved through the Water table and inextended position enabling said means to overlie the water table.

2. A crown block structure adapted to bepositioned on top of the watertable of a derrick comprising a plurality of sheaves, meansforsupporting said sheaves, said means comprising a plurality of partsmovable with respect to each other from an extended position in linewitheach other to a collapsed position, said .parts in collapsed positionenabling said means to be moved through the water table and in extendedposition enabling said means to overlie the water table, and acable linereeved around said sheaves of said crown block before said crown blockis raised into position on said derrick.

3. A -crown block structure adapted to bepositioned on top of the watertable of -.a derrick comprising a plurality of sheaves, means forsupporting said sheaves, said means comprising a plurality of partsmovable with respect toeach other froman extended position in line witheach other to a collapsed position, said parts in collapsed positionenablingsaid meansto be movedthrough the water table .and in extended,position enabling said means to overlie the Water table, and a. cableline reeved around said sheaves of .said crown block and the sheaves ofa travelling. block .before said'crown block is raised into position onsaid water table.

JOHN W. MACCLATCHIE.

